* syscalls.cc (_isatty): Define as an alias to isatty to override newlib

version.
* thread.cc (pthread_kill): Deal with signal 0 as per POSIX and also avoid
manipulating an invalid thread.

1 files changed, 18 insertions, 2 deletions

diff --git a/winsup/cygwin/thread.cc b/winsup/cygwin/thread.cc
index d78bbbb9c..7e52e3be9 100644
--- a/winsup/cygwin/thread.cc
+++ b/winsup/cygwin/thread.cc
@@ -2640,8 +2640,24 @@ pthread_kill (pthread_t thread, int sig)
   si.si_code = SI_USER;
   si.si_pid = myself->pid;
   si.si_uid = myself->uid;
-  thread->cygtls->set_threadkill ();
-  int rval = sig ? sig_send (NULL, si, thread->cygtls) : 0;
+  int rval;
+  if (!thread->valid)
+    rval = ESRCH;
+  else if (sig)
+    {
+      thread->cygtls->set_threadkill ();
+      rval = sig_send (NULL, si, thread->cygtls);
+    }
+  else
+    switch (WaitForSingleObject (thread->win32_obj_id, 0))
+      {
+      case WAIT_TIMEOUT:
+	rval = 0;
+	break;
+      default:
+	rval = ESRCH;
+	break;
+      }
 
   // unlock myself
   return rval;